The invention relates to cable guiding on a rack suitable for housing connections of cables in a telecommunications or data communications network. The invention more particularly relates to a rack including cable guides, to a cable guide for use on such a rack, to a flat pack for assembling on site into such a rack and to a method of making cable connections in such a rack. The rack may be clad with panels and thus take the form of what is referred to herein as an enclosure, but it may also be used without such panels.
Racks commonly have many cables passing in and out of them and it is desirable to maintain those cables in an orderly manner and to guide them along suitable paths. For that purpose it is already known to provide cable guides of various kinds on a rack. Such cable guides may also serve the purpose of enabling the length of a particular cable path to be adjusted to accommodate a particular length of cable; such an arrangement may for example be useful when connections are to be made between two racks placed side-by-side.
Desirably, a cable guidance system is simple and inexpensive but also effective and able to adapt to a wide variety of different conditions which may arise during use. Hitherto it has proved difficult to provide a rack that includes a cable guidance system that provides even the majority of the desirable features just referred to and the present invention seeks to overcome or mitigate that problem.
The present invention provides in a first aspect a rack suitable for housing connections of cables in a telecommunications or data communications network, the rack including a plurality of cable guides and a plurality of cable guide mountings at each of which the cable guides are capable of being mounted, wherein the cable guides are arranged to be detachably mountable at the plurality of cable guide mountings and are able to be detached and attached without the use of tools.
The present invention further provides in the first aspect a rack suitable for housing connections of cables in a telecommunications or data communications network, the rack including a plurality of cable guides and a plurality of cable guide mountings at each of which the cable guides are capable of being fixed, wherein the cable guides are arranged to be detachably mountable at the plurality of cable guide mountings and are able to be detached and attached by rotation of the cable guide.
By providing a rack with cable guides that can readily be detached and attached, it immediately becomes easy to adjust the cable guiding system to different configurations for different purposes. If the cable guides are able to be detached and attached without having to rely upon tools, that further facilitates the alteration of the cable guiding system.
Preferably each cable guide includes a mounting portion for engagement with a respective cable guide mounting and a guiding portion providing one or more guide surfaces for a cable. The mounting system for mounting the cable guides may take various forms but it is especially preferred that the mounting portion includes a mounting head connected to the cable guide by a neck and the cable guide mountings are defined by holes in one or more generally lamellar parts of the rack, the head being insertable in a first orientation of the cable guide through a selected one of the holes defining the cable guide mountings and then rotatable to a second orientation in which the head is unable to pass back through the selected hole. With such a system it is a very simple operation, without any tools, to attach a cable guide to a mounting on the rack or to detach it from such a mounting. Preferably rotation of the cable guide in use serves to secure the guide to a lamellar part around the hole through which the guide is inserted; if desired the rotation can cause a progressively increasing clamping action. In that way, simple rotation of the cable guide by hand can lead to a secure fixing of the guide on the rack.
Preferably, the cable guiding portion of each cable guide is generally in the form of a rod; preferably the rod is of substantially circular cross-section.
It is an especially advantageous feature of the invention that each guide preferably includes a cable retaining portion at the opposite end of the guiding portion to the mounting portion. The cable retaining portion advantageously projects laterally outwards and may take various forms: for example, it may be defined by a flange; the flange may be circular and may extend around the whole of the cable guiding portion at a substantially constant width. Alternatively and advantageously the width of the flange may vary around the cable guide and may not exist in some regions. Thus the cable retaining portion may project laterally outwardly from the guiding portion substantially further in one or more directions than in other directions.
The cable retaining portion may be fixed to the cable guiding portion and may be formed integrally therewith. According to an especially preferred feature of the invention, however, the cable retaining portion is adjustably mounted on the cable guiding portion; preferably it is rotatably mounted on the cable guiding portion. Preferably the cable retaining portion is arranged to be mounted on the cable guiding portion by fitting it over a free end of the cable guiding portion. The cable retaining portion may be continuously and infinitely adjustable around the cable guiding portion but it is preferred that it is adjustable between a plurality of predetermined different positions relative to the cable guiding portion. By providing the adjustment facility referred to above it becomes possible to arrange for the cable retaining portion to present little or no obstruction to the initial placing of a cable around the guide but thereafter, following adjustment of the retaining portion, to obstruct removal of the cable and thereby retain the cable in its desired location.
The spacing of the cable guides and the amount of the lateral projection of the cable retaining portion may be chosen to be such that when the projections are adjusted to a position in which they are directed towards one another, the space between them is so small that a cable is unable to pass between them; indeed the projections may touch one another.
In addition to the cable retaining portion, a guide may further include one or more cable dividers projecting radially from the guiding portion of the guide. The cable dividers may be in the form of discs. Generally it is preferred that the discs are circular and extend around the whole of the cable guiding portion at a substantially constant width, but it is also possible for the lateral projection to be greater in some directions than in others.
The cable dividers may be a friction fit on the cable guiding portion of the guide.
The cable dividers may have any appropriate features of the cable retaining portion described above.
Parts of the cable guides may be apertured to facilitate the connection of cable ties between adjacent parts of the same cable guide or parts of adjacent cable guides.
The cable guide mountings may be fixed to one or more of the frame members of the rack and they may also be fixed to one or more other members mounted on the frame members. Such other members may extend vertically, horizontally across all or part of the frame between one side and the other or horizontally through all or part of the depth of the frame between the back and the front; usually the cable guide mountings are provided on a vertical face of a member, but they may also be provided on a horizontal face. Thus there is considerable flexibility regarding the locations of the cable guide mountings. Preferably at least some of the cable guide mountings are arranged in one or more rows, more preferably in one or more horizontal rows and/or one or more vertical rows.
The rack may further include cables which are connected to terminals in the enclosure, the paths of one or more of the cables being guided by one or more of the plurality of cable guides which are mounted on at least some of the cable guide mountings.
The cable retaining feature of the cable guide has been described above only in combination with the feature of detachability of the guide but can also be employed without that feature. Thus the invention further provides in a second aspect, a rack suitable for housing connections of cables in a telecommunications or data communications network, the rack including a plurality of cable guides, each guide including a generally rod-shaped guiding portion extending outwardly from a mounted end to a free end, and a cable retaining portion at the free end of the rod-shaped guiding portion, the cable retaining portion extending laterally beyond the guiding portion in one or more radial directions and being rotatable to adjust the direction of said one or more radial directions.
The rack according to the second aspect of the invention may further comprise any of the features of the rack according to the first aspect of the invention.
The term xe2x80x9cenclosurexe2x80x9d used above should not be taken to imply that there are continuous walls defining a fully closed space. Often it is desirable for there to be panels enclosing a substantial part of the enclosure in order both for the connections to be protected and for persons to be protected from the connections. It should be understood, however, that it is within the scope of the present invention to provide an enclosure with only some panels or a rack without any panels.
The present invention further provides a flat pack comprising a plurality of parts for assembly on site into a rack as defined above.
The invention still further provides a method of making cable connections in a rack as defined above, including the step of guiding a cable around one or more of the plurality of cable guides. In the case where the cable retaining portion is adjustable, the cable is preferably placed around a cable guide and thereafter the guide is adjusted to cause a part of the cable retaining portion to overlie part of the cable.